Vacuum support inspection head



Jan. 2, 1968 v "r. E. SMITH r 3,360,983

VACUUM SUPPORT INSPECTION HEAD Filed Feb. 8, 1965 3 Sheets-Sheet 1INVENTOR THOMAS E- SMITH Jan. 2, 1968 "r. E. SMITH 3,360,933 I VACUUMSUPPORT INSPECTION HEAD Filed Feb. 8,1965 a Sheets-Shee1; 2

INVENTOR THOMAS E. SMITH Jan. 2, 1968 T. E. SMITH 3,360,983

VACUUM SUPPORT INSPECTION HEAD Filed Feb. 8, 1965 s Sheets-Sheet sINVENTOR THOMAS -E- SMITH ATTORNEY United States Patent 3,360,983 VACUUMSUPPORT INSPECTION HEAD Thomas E. Smith, Lancaster County, Pa., assignorto Armstrong Cork Company, Lancaster, Pa., a corporation of PennsylvaniaFiled Feb. 8, 1965, Ser. No. 431,055 7 Claims. (Cl. 73-453) ABSTRACT OFTHE DISCLOSURE An inspection device for the testing of the linings forclosures. The liner in a closure is tested by placing a plunger with arigid ring adjacent the upper surface of the liner to form a pocket inwhich a vacuum may be pulled. A sleeve around the plunger presses on theouter edge of the closure. The direction of the pressure on the outeredge of the closure and the pressure on the center of the closure due tothe existence of a vacuum result in a testing of the sealing quality ofthe liner.

The inspection apparatus of the prior art generally comprises valved,vacuum inspection heads for inspecting articles such as closure liners.Such construction results in relatively complicated inspection headshaving internally moving parts including spring biased valve stems. Suchapparatus is subject to wear and accumulation of foreign matter whichmay prevent proper opening and closing of the valve associatedtherewith. Malfunctions resulting from these causes require periodicmaintenance as well as adjustment in order to keep said apparatus inoperable condition.

With the development of plastic closure liners including sealing ringsof polyethylene and polyvinyl plastisol, there arose a need forinspection apparatus which will accept closures having liners which willprovide a commercially acceptable seal with regard to the package towhich they will be applied, while rejecting those closures having linerswhich will not provide such a seal. The inspection apparatus of theprior art does not provide means to inspect closure liners having theaforementioned sealing rings.

Accordingly, it is an object of the present invention to provideinspection apparatus which is valveless in nature.

Another object of the present invention is to provide inspectionapparatus having means to inspect sealing rings.

Other objects of the present invention will be apparent from thedetailed description thereof with reference to the drawings wherein:

FIGURE 1 is a view in elevation of an inspection apparatus according tothe present invention;

FIGURE 2 is a side view in elevation with portions broken away of theinspection apparatus shown in FIG- URE 1;

FIGURE 3 is a partial, sectional view of the inspection apparatus shownin FIGURE 2 taken along line 3-3 therein;

FIGURE 4 is a partial, sectional view of the inspection apparatus shownin FIGURE 2 taken along line 4-4 therein;

FIGURE 5 is a partial, sectional view of the inspection apparatus shownin FIGURE 2 taken along line 5 --5 therein;

FIGURE 6 is a partial, sectional view in elevation of an inspection headaccording to the present invention;

FIGURE 7 is an enlarged, partial, sectional view in elevation of thelower portion of the inspection head of FIGURE 6;

FIGURE 8 is a bottom view of the inspection head shown in FIGURE 7;

FIGURE 9 is a sectional view in elevation of an inspection headaccording to the present invention in an inspecting position withrespect to a closure having a sealing ring;

FIGURE 10 is a partial View in elevation with portions broken away of aninspection head according to the present invention in an inspectionposition with respect to a. closure having a sealing ring with a defecttherein;

FIGURE ll is a partial view in elevation of an inspection head accordingto the present invention in an inspection position with respect to aclosure having a defective sealing ring;

FIGURE 12 is a plan view of a closure having a sealing ring with anout-of-round portion; and

FIGURE 13 is a partial, sectional view in elevation of an inspectionhead according to the present invention in an inspection position withrespect to a closure having a defective sealing ring.

Referring now to FIGURES 1 and 2, there is shown inspection apparatushaving a base 20 and a vertical support member 21 extending upwardlytherefrom. Vertical support member 21 has an intermediate guide member22 extending outwardly from vertical support member 21. Intermediateguide member 22 has a vertical bore 23 extending partially therethroughfrom the upper surface of said intermediate guide member to a pointwhere said bore 23 communicates with a counterbore 24 which extendsupwardly from the lower surface of said intermediate guide member 22.

A chuck 25 is reciprocatingly received by bore 23. Chuck 25 has anupper, closure-receiving cavity 26. Chuck 25 has a lower, bifurcated end27 which receives cam roller 28. Cam roller 28 is mounted for rotationabout pin 29 which is supported by bifurcated end 27 of chuck 25. Chuck25 is provided with a flanged portion 30 which is located nearbifurcated end 27. A spring 31 surrounds chuck 25 in counterbore 24 andextends downwardly therefrom to flange 30. Spring 31 acts on flange 30to bias chuck 25 in a downward direction.

Block 32 extends upwardly from base 20. Cam 33 is secured to shaft 34which is supported for rotation in suitable bearings in block 32. Theperiphery of cam 33 underlies and is substantially co-planar with camroller 28. Spring 31 biases chuck 25 and cam roller 28 into contact withthe periphery of cam 33. A conventional, variable speed motor, clutch,and coupling mechanism 35 may be provided to rotate cam 33. Rotation ofcam 33 will cause chuck 25 to reciprocate in a vertical direction. As isseen in FIGURE 3, bore 23 and chuck 25 are rectangular in cross sectionto prevent chuck 25 from twisting in bore 23 and resultant misalignmentof cam roller 28 and cam 33.

A lateral guide member 36 extends outwardly from vertical support member21 in overlying relationship to intermediate guide member 22. Upperguide section 37 extends upwardly from lateral guide member 36. Bore 38extends downwardly through upper guide section 37 into lateral guidemember 36. Bore 38 has an upper threaded portion 39. Bore 40 has asmaller diameter than bore 38 and extends upwardly from the lowersurface of lateral guide member 36 into communication with bore 38.Bores 38 and 40 are aligned with bore 23. A vertical slot 41communicates bore 38 with the exterior of upper guide section 37.

An inspection head assembly 42 is reciprocatingly received by bore 38and bore 40. Inspection head assembly 42 has an upper body 43, a neck 44depending from said upper body 43, an annular collar 45 adjustablysecured to and extending outwardly from said neck 44 at an intermediatelocation thereon, and a lower body portion 46 depending from said neck44. Annular collar 45 is secured to neck 44 by conventional set screwmeans.

Upper body 43 is located in bore 38 with the upper portion of neck 44extending downwardly through bore 40. The annular flange formed by thejuncture of bores 38 and 40 cooperates with the flange formed by thejuncture of upper body 43 and neck 44 to serve as a lower limit withregard to movement of inspection head assembly 42. As shown in FIGURE 4,upper body 43 and bore 38 may be rectangular in cross-section to preventmisalignment between these elements. A spring 47 is located in bore 38above upper body 43. A threaded plug is received in upper threadedportion 39. Plug 48 may be adjusted within bore 38 to compress spring 47and bias upper body 43 and inspection head assembly 42 into itslowermost position against the annular flange formed by the juncture ofbores 38 and 40.

An annular sleeve 49 surrounds lower body 46. Sleeve 49 has a bore 50which surrounds the lower portion of neck 44 as shown in FIGURES 2 and6. Sleeve 49 also has a bore 51 which surrounds lower body 46. Theflange formed by the juncture between bores 50 and 51 cooperates withthe shoulder formed by the juncture of neck 44 and lower body 46 tolimit downward movement of sleeve 49 with respect to lower body 46. Aspring 52 surrounds neck 44 between collar 45 and the upper portion ofsleeve 49 to bias sleeve 49 into its lowermost position with respect tolower body 46. It should be noted that when sleeve 49 is in itslowermost position, the lower surface thereof is below the lowestportion of lower body 46.

As shown in FIGURES 6 and 7, inspection head assembly 42 is providedwith a central bore 53 which communicates with orifice 54 located in thelower portion of lower body 46. Orifice 54 communicates bore 53 with theexterior of the inspection head. The upper portion of bore 53communicates with the lateral passage 55 which in turn communicates witha nipple 56 secured to upper body 43. It should be noted that nipple 56is received in slot 41 and is free to move vertically therein. Suitableconduit means 57 of a flexible nature connect nipple 56 with aconventional low pressure or vacuum source 58.

The lower portion of lower body 46 forms the closure orarticle-receiving portion. A rigid, annular inspection or gauge ring 59is located on the lower face of lower body 46 in surroundingrelationship to orifice 54. Ring 59 is of a predetermined size and shapecorresponding to a surface which is to be sealed by the sealing liner tobe tested and inspected by the inspection head. A plurality ofcircumferentially spaced, arcuate feeler segments 60 extend downwardlyfrom the lower body 46 to a point below the lowermost extent of ring 59.Segments 60 are located between ring 59 and orifice 54 in surroundingrelationship to said orifice 54. A similar set of circumferentiallyspaced, arcuate feeler segments 61 extend from the lower portion oflower body 46 to a point below ring 59 but above the lowermost extent ofsegments 60. Segments 61 are positioned on the outer side of ring 59.The particular configuration of the inspection gauge ring 59 and feelersegments 60 and 61 shown in FIGURES 6 and 7 is that which may be used toinspect a closure with a plastisol liner of a specific geometricconfiguration.

The operation of the device will now be described. A closure 62 having asealing ring 63 to be inspected is placed in chuck cavity 26. Cam 33 isrotated to cause chuck 25 and closure 62 to move upwardly whereupon theperiphery of closure 62 will contact the lower periphery of sleeve 49.Continued upward movement of chuck 25, and closure 62 will cause sleeve49 to be moved upwardly with respect to lower body 46 against the biasof spring 52 until sealing ring 63 contacts inspection ring 59.Continued upward movement of closure 62 with respect to inspection head42 will cause rigid ring 59 to seat itself in resilient sealing ring 63as shown in FIG- URE 9, for example. Spring 47 biases inspection head 42downwardly to maintain contact between ring 59 and sealing ring 63.

It should be noted that there are no valves between the vacuum source 58and orifice 54, thereby providing a valveless, constant vacuumarrangement. If the orifice 54 is quite small on the order of .014 indiameter, for example, air flow through said orifice when no closure isin inspection position will be quite small. This small air flow willallow the use of a small vacuum source 58. In any event, once ring 59 isseated in sealing ring 63, the air in the space between lower body 46and the inside of closure 62 interiorly of sealing ring 63 will beevacuated by the vacuum source through orifice 54, bore 53, passage 55,nipple 56, and conduit means 57.

If there is an adequate seal between inspection ring 59 and sealing ring63, there will be no appreciable air flow through orifice 54 once theinterior of the closure 62 has been evacuated. The difference inpressure between the inner portion of the closure which has beenevacuated and the outer portion thereof acts on the closure 62 in amanner which provides a retention force tending to hold the closure onthe inspection head assembly 42. This force will be at a maximum whenthere is a perfect seal between the sealing ring 63 and the inspectionring 59 and consequently, no air flow through orifice 54. The spring 52is chosen and the effect thereof adjusted by means of adjustable collar45 so that the force acting on sleeve 49 tending to strip closure 62from the inspection head will be less than that maximum force tending toretain an acceptable closure on the inspection head. Thus a closurehaving an acceptable sealing ring will remam in contact with theinspection head when chuck 25 is removed therefrom. This closure maythen be manually or otherwise stripped from the inspection head.

If sealing ring 63 has a defect such as a low spot 64, for example asshown in FIGURE 10, and said low spot 64 is of such an extent as toprevent the sealing between inspection ring 59 and sealing ring 63,there will be a flow of air through said low spot 64 into the interiorof the closure 62. In such a case, the pressure differential between theinside of the closure 62 adjacent the inspection head and the outside ofsaid closure 62 will be less than the maximum value noted above wherethere is no leakage. The reduced pressure differential will result in areduced retention force acting on closure 62 to retain it in contactwith the inspection head. Thus, where the retention force is less thanthe stripping force exerted by spring 52 through sleeve 49 on closure62, the closure will not be retained on the inspection head should thechuck 25 be.

moved downwardly to the position shown in FIGURE 2. By adjusting thecollar 45 on neck 44 the effect of the spring on sleeve 49 and theresultant stripping force may be varied. It can be determined byexperimentation the proper amount of stripping force that is required toreject closures having sealing liners which have defects serious enoughto preclude a satisfactory and/or commercially acceptable seal when theyare applied to articles which are to be sealed.

From a practical standpoint, the sensitivity of the device can becontrolled by controlling the size of the orifice; and the properorifice size may be determined according to the results ofexperimentation which will show which size orifice will reject closureshaving sealing rings which will not seal properly when applied tocontainers which are to be sealed. It is to be understood that the useof a relatively small orifice on the order of .010" to .020" indiameter, for example, is desirable to keep the air flow through theorifice at a minimum and to obtain the desired sensitivity of operation.Further, the size of the passages and conduit means between the orificeand the vacuum or low pressure source should be sufficiently greaterthan the orifice size such that the pressure drop on the downstream sideof the orifice will be negligible. This arrangement will provide asubstantially constant vacuum or low pressure reference at thedownstream side of the orifice. The use of a small size orifice andrelatively larger passage and conduit means as noted above will allow arelatively small vacuum or low pressure source to be used, and no valveor other flow control means will be required between the orifice and thelow pressure or vacuum source. The omission of such a valve or flowcontrol means between the orifice and vacuum or low pressure sourceprovides greater accuracy of inspection as well as omitting theoperating and maintenance problems associated with such a valve or flowcontrol means. However, it should be noted that this arrangement doesnot preclude the use of an orifice which is adjustable in nature. Thus,this apparatus can accurately determine the acceptability of sealingrings in closures.

In the prior discussion, it was noted that the inspection ring 59 willnot seat properly if the sealing ring 63 contains a defect such as a lowspot 64, which may be sufficient to prevent adequate sealing action.Similarly, the ring 59 will detect other flaws and prevent scaling inthe same manner. In fact, any defect in a given sealing ring which willallow a predetermined unacceptable air flow therethrough when said ringis placed adjacent the inspection ring 59 will cause said sealing ringand its associated closure to be stripped from the inspection head andrejected. In the case of out-of-round sealing rings such as shown inFIGURE 12, for example, a feeler segment 61 will contact the out-ofroundportion 65 of the sealing ring and prevent the inspection ring 59 fromsealing therewith. In this case, air will be allowed to flow through thespaces between segments 61, between inspection ring 59 and sealing ring63, and through the spaces between segments 60 to orifice 54. As in theexamples noted above, the pressure differential for sealing rings havinga degree of out-of-roundness which will produce an unacceptable sealwhen applied to a container will not be sufficient to provide a forcewhich will retain the closure in contact with the inspection head, andsaid closure will be stripped from said head and rejected. It isapparent that outer segments 61 will also prevent a proper seal beingmade between inspection ring 59 and sealing rings which have greaterthan-max mum acceptable diameter such as that shown in FIGURE 11.Conversely, if a particular sealing ring has a diameter which is belowthe minimum acceptable diameter, the segments 60 will prevent thesealing ring 63 from being seated on inspection ring 59. In each case,the closure having the defective sealing ring will be stripped from theinspection head by sleeve 49 and rejected.

In the example shown in FIGURE 13, where the sealing ring 66 does nothave sufficient height, feeler segments 60 will prevent inspection ring59 from making a proper seal with sealing ring 66 thereby allowing airto pass through the spaces between segments 61 and segments 60 to theinterior of the closure. As in the cases noted above, such air flow willprovide a relatively low pressure differential between the inside andthe outside of the closure which will result in a retention force whichis insufficient to retain the closure in contact with the inspectonhead. Such a defective closure will be stripped from the head and remainin the chuck cavity 26. The same action would occur if the closure beingtested was devoid of sealing material.

Thus, it is apparent that the device of the present invention providesfor accurate inspection of sealing rings in articles. Further, thedevice of the present invention provides a relatively uncomplexapparatus for the inspection of sealing rings. The apparatus accordingto the present invention is economical to manufacture and maintain inrelation to the prior art devices. It should be noted that the shape andsize of inspection ring and feeler means depend upon the size and shapeof the sealing ring, closure, or article to be inspected. The device ofthe present invention may be used to inspect defects in many types ofsealing means in articles and is not limited to inspecting sealing ringsin closures or a particular type of sealing ring in a particular type ofclosure. Similarly, the inspection apparatus of the present inventionmay be used to inspect sealing means of many different types ofmaterials and is not limited to the inspection of those materialsdescribed herein. It is to be understood that all elements including theinspection head may be sectionalized and secured together withconventional fastening means for assembly purposes as would be obviousto a skilled mechanic or machinist. It is to be understood that theshapes, s'zes, andrelative location, composition, and materials ofconstruction of the elements of the present invention may be varied, andthat the present invention is not limited to the specific embodimentshown and described herein. For example, the number of arcuate segmentsand positioning thereof as well as the spaces therebetween may be variedand staggered without departing from the scope of the present invention.

Various modifications of the present invention will occur to thoseskilled in the art without departing from the spirit and scope thereofas defined in the claims.

I claim:

1. An inspection head comprising a body including an article-receivingportion, orifice means on said article-receiving portion, passage meansin said body connecting said orifice means with the exterior of saidbody at a point spaced from said article-receiving portion, rigid,annular, gauge means on said article-receiving portion surrounding saidorifice means, sleeve means surrounding said body adjacent saidarticle-receiving portion and adjustable bias means to bias said sleevemeans against the peripheral edge portion of the article being testedand to provide a force tending to dislodge said article from its testposition, said passage mean connected to the chamber formed by thearticle, the gauge means and the article-receiving portion to provide aforce opposing the first-mentioned force whereby leakage past the gaugeand article causes a force differential and rejection of the article.

2. An inspection head according to claim 1 further comprising innerfeeler means located on said article-receiving portion between saidorifice means and said rigid, annular gauge means, said feeler meansextending outwardly from said article-receiving portion.

3. An inspection head according to claim 2 further comprising outerfeeler means located on said article-receiving portion outwardly of saidannular gauge means.

4. An inspection head according to claim 1 further comprising feelermeans located on said article-receiving portion outwardly of saidannular gauge means.

5. A valveless inspection head comprising a body including anarticle-receiving portion, orifice means on said article-receivingportion, valveless passage means in said body connecting said orificemeans with the exterior of said body at a point spaced from saidarticle-receiving portion, rigid, annular, gauge means on saidarticle-receiving portion surrounding said orifice means, sleeve meanssurrounding said body adjacent said article-receiving portion, andadjustable bias means to bias said sleeve means against the peripheraledge portion of the article being tested and to provide a force tendingto dislodge said an ticle from its test position, said passage meansconnected to the chamber formed by the article, the gauge means and thearticle-receiving portion to provide a force opposing thefirst-mentioned force whereby lealcage past the gauge and article causesa force differential and rejection of the article.

6. A valveless inspection head according to claim 5 further comprisingfeeler means located on said article-receiving portion.

7. An inspection head comprising a body including an article-receivingportion, orifice means on said articlereceiving portion, passage meansin said body connecting said orifice means with the exterior of saidbody at a point spaced from said article-receiving portion, annulargauge means on said article-receiving portion surrounding 7 8 saidorifice means, sleeve means surrounding said body ad- References Cited jacent said article-receiving portion, and adjustable bias UNITED STATESPATENTS means to 'bias said sleeve means against the peripheral edgeportion of the article being tested and to provide gurkett a forcetending to dislodge said article from its test posi- 5 2901906 9/1959BS2 1 73 37 mom, said passage means connected to the chamber formed3:O15:388 1/1962 Wilckens 73 45.3

by the article, the gauge means and the article-receiving portion toprovide a force opposing the first-mentioned LOUIS PRINCE PrimaryExaminer force whereby leakage past the gauge and article causes a forcedifferential and rejection of the article. 10 NOLTON Assistant Emmmer'

